Flat panel display devices include liquid crystal displays (LCDs), plasma display panels (PDPs), organic light emitting displays (OLEDs), field effect displays (FEDs), eletrophoretic displays (EPDs), and electrowetting displays (EWDs). An electrowetting display device includes an electrowetting display panel that displays images using electrowetting techniques.
An electrowetting display panel generally includes a first substrate provided with a first electrode, a second substrate provided with a second electrode and facing the first substrate, and an electrowetting layer interposed between the first substrate and the second substrate. The electrowetting layer generally includes fluids that do not mix with each other. One of the fluids has electrical conductivity or polarity, and at least one of the fluids has optical properties such as absorbing, reflecting or filtering light rays. Therefore, images can be displayed by controlling the optical characteristics of the light with the electrowetting layer, wherein the relative positions of the fluids are controlled using the electric field formed between the first and the second electrodes.
To manufacture such an electrowetting display panel, the fluids are provided on one of the first substrate or the second substrate and then the first substrate and the second substrate are coupled together. Since the fluids do not mix with each other but actually repel each other, a portion of the fluids may not be retained between the first substrate and the second substrate and may actually be expelled out from between the first substrate and the second substrate. The expelled fluids can contaminate an apparatus used for coupling the substrates and/or raise the manufacturing cost due to unnecessary waste of the fluids.